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Graphene has attracted widespread attention for development of high-performance lithium-ion battery anode materials. In this paper, the lithium storage mechanisms of multilayer graphene, few-layer graphene, and reduced graphene oxide electrodes are investigated, and the influences of layers and defects in the microstructure are analyzed. The evolution of microstructure deformation of different graphene electrodes, combined with the diffusivity and distribution of lithium, is systemically investigated by in-situ Raman spectroscopy during lithiation and delithiation. The results show that graphene electrodes with different structures exhibit different mechanical behaviors and thus different lithium storage capacities. Mechanical analysis indicates that although the surfaces and defects are active, interlayer lithium insertion contributes the most lithium storage capacity. As the number of graphene layers increases and/or defects decrease, more interlayer spaces would be provided. Thus, the lithium storage capacity of multilayer graphene is significantly higher than those of few-layer graphene and reduced graphene oxide. An in-depth understanding of the effect of the microstructure on the lithium storage behavior of graphene electrodes will provide an experimental basis for development of high-performance graphene electrodes. [Display omitted] • Li storage behavior of graphene electrodes with different layers and defects. • Comprehensive experiments to measure strain, diffusivity, and Li distributions. • Interlayers of graphene provides more Li storage sites than surfaces and defects. • Multilayer graphene has a larger Li capacity because of more interlayer spaces. [ABSTRACT FROM AUTHOR]

Mesoporous carbon with a high specific surface area (1,342.8 m²/g) and a high mesopore volume (1.396 cm³/g) was prepared from Novalac phenol–formaldehyde resin as a carbon source, with F127 and nanosized silica as templates, followed by carbonization at high temperature. For comparison, other mesoporous carbon materials were prepared with only one template. The application of these mesoporous carbon materials and a commercial activated carbon for ciprofloxacin (CIP) removal from aqueous solution was investigated. At a low CIP concentration, the maximum adsorption of CIP on the mesoporous carbon was as high as 243.91 mg/g, which was the largest among these carbon materials and higher than that in literature. The adsorption capacities of these carbon adsorbents increased with an increase in mesopore volume. The equilibrium adsorption data were well described by the Langmuir isotherm. The adsorption kinetics followed a pseudo-second-order kinetic model. The effect of pH on the CIP adsorption was studied to investigate the adsorption mechanism. [ABSTRACT FROM AUTHOR]

Vincamine, a monoterpenoid indole alkaloid which had been marketed as nootropic drugs for the treatment of cerebral insufficiencies, is widely found in plants of the Apocynaceae family. Nerium indicum is a plant belonging to the Apocynaceae family. So, the purpose of this research was designed to investigate the vincamine alkaloids producing endophytic fungi from Nerium indicum , Apocynaceae. 11 strains of endophytic fungi, isolated from the stems and roots of the plant, were grouped into 5 genera on the basis of morphological characteristics. All fungal isolates were fermented and their extracts were preliminary screened by Dragendorff’s reagent and thin layer chromatography (TLC). One isolated strain CH1, isolated from the stems of Nerium indicum , had the same R f value (about 0.56) as authentic vincamine. The extracts of strain CH1 were further analyzed by high performance liquid chromatography (HPLC) and liquid chromatograph-mass spectrometry (LC–MS), and the results showed that the strain CH1 could produce vincamine and vincamine analogues. The acetylcholinesterase (AchE) inhibitory activity assays using Ellman’s method revealed that the metabolites of strain CH1 had significant AchE inhibitory activity with an IC 50 value of 5.16 μg/mL. The isolate CH1 was identified as Geomyces sp. based on morphological and molecular identification, and has been deposited in the China Center for Type Culture Collection (CCTCC M 2014676). This study first reported the natural compounds tabersonine and ethyl-vincamine from endophytic fungi CH1, Geomyces sp. In conclusion, the fungal endophytes from Nerium indicum can be used as alternative source for the production of vincamine and vincamine analogues. [ABSTRACT FROM AUTHOR]

Exposure to environmental toxins such as pesticides is implicated in increasing Alzheimer's disease risk. In this study, we investigated the long-term effects of paraquat exposure on cognition of Alzheimer's disease animal model APP/PS1 mice and wild-type (WT) mice. Our results showed that APP/PS1 mice had exacerbated cognition impairment and elevated Aβ levels at 5 months after paraquat exposure, and that WT mice had cognition impairment at 5 and 16 months after paraquat exposure. In addition, increased mitochondrial oxidative stress and augmented brain inflammation were observed in both paraquat-exposed APP/PS1 mice and WT mice. Interestingly, activation of NLRP3 inflammasome, which triggers inflammation in response to mitochondrial stress, was enhanced in paraquat-exposed mice. Moreover, transgenic mice overexpressing Prdx3, a key enzyme in detoxifying mitochondrial H 2 O 2 , had suppressed NLRP3 inflammasome activation, reduced brain inflammation, and attenuated cognition impairment after paraquat exposure. Together, our results indicate that NLRP3 inflammasome activation induced by mitochondrial reactive oxygen species plays a key role in mediating paraquat-induced long-term cognition decline by elevating brain inflammation. [ABSTRACT FROM AUTHOR]

Increased mitochondrial hydrogen peroxide (H 2 O 2 ) is associated with Alzheimer's disease and brain aging. Peroxiredoxin 3 (Prdx3) is the key mitochondrial antioxidant defense enzyme in detoxifying H 2 O 2 . To investigate the importance of mitochondrial H 2 O 2 in age-associated cognitive decline, we compared cognition between aged (17–19 months) APP transgenic mice and APP/Prdx3 double transgenic mice (dTG) and between old (24 months) wild-type mice and Prdx3 transgenic mice (TG). Compared with aged APP mice, aged dTG mice showed improved cognition that was correlated with reduced brain amyloid beta levels and decreased amyloid beta production. Old TG mice also showed significantly increased cognitive ability compared with old wild-type mice. Both aged dTG mice and old TG mice had reduced mitochondrial oxidative stress and increased mitochondrial function. Moreover, CREB signaling, a signaling pathway important for cognition was enhanced in both aged dTG mice and old TG mice. Thus, our results indicate that mitochondrial H 2 O 2 is a key culprit of age-associated cognitive impairment, and that a reduction of mitochondrial H 2 O 2 could improve cognition by maintaining mitochondrial health and enhancing CREB signaling. [ABSTRACT FROM AUTHOR]

Oxidative damage including lipid peroxidation is widely reported in Alzheimer's disease (AD) with the peroxidation of phospholipids in membranes being the driver of ferroptosis, an iron-dependent oxidative form of cell death. However, the importance of ferroptosis in AD remains unclear. This study tested whether ferroptosis inhibition ameliorates AD. 5xFAD mice, a widely used AD mouse model with cognitive impairment and robust neurodegeneration, exhibit markers of ferroptosis including increased lipid peroxidation, elevated lyso-phospholipids, and reduced level of Gpx4, the master defender against ferroptosis. To determine if enhanced defense against ferroptosis retards disease development, we generated 5xFAD mice that overexpress Gpx4, i.e., 5xFAD/GPX4 mice. Consistent with enhanced defense against ferroptosis, neurons from 5xFAD/GPX4 mice showed an augmented capacity to reduce lipid reactive oxygen species. In addition, compared with control 5xFAD mice, 5xFAD/GPX4 mice showed significantly improved learning and memory abilities and had reduced neurodegeneration. Moreover, 5xFAD/GPX4 mice exhibited attenuated markers of ferroptosis. Our results indicate that enhanced defense against ferroptosis is effective in ameliorating cognitive impairment and decreasing neurodegeneration of 5xFAD mice. The findings support the notion that ferroptosis is a key contributor to AD pathogenesis. [Display omitted] • Symptomatic 5xFAD mice exhibit markers of ferroptosis. • 5xFAD neurons' capacity to detoxify lipid ROS is enhanced by Gpx4, the master defender against ferroptosis. • 5xFAD mice with overexpression of Gpx4 show improved cognition and ameliorated neurodegeneration. • Markers of ferroptosis are attenuated in 5xFAD mice with overexpression of Gpx4. [ABSTRACT FROM AUTHOR]

Graphene and N-doped graphene have been widely used for improving the cycling performance of silicon based anode for advancing lithium-ion battery's performance due to their capabilities in suppressing the volume expansion of Si nanoparticles which is responsible for the rapid and irreversible degradation. While it is known that there are pyridinic and pyrrolic nitrogen motifs in the N-doped graphene, there have been no studies of the controllability and optimization of their ratio during N-doping and how it influences on the battery performance. We demonstrate here for the first time that the pyridinic-to-pyrrolic nitrogen ratio is not only controllable in N-doped graphene but also there is an optimal ratio for the enhancement of battery performance. The pyrrolic type N as the major doping form in Nano-Si@NG is shown to deliver a reversible capacity of 950 mA h g−1 over 100 cycles in Li-ion battery performance test, a much better capacity retention than that of bare Si nanoparticle. The degree and type of N-doping in the nanocomposite were shown to be two dominated factors influencing the lithium storage properties, which was supported by X-ray photoelectron spectroscopy (XPS) identification of three types of N-doping structures. The result is further substantiated by density functional theory (DFT) calculation of the energy barrier for diffusion of Li ion in the nanocomposite structure, revealing the smallest diffusion barrier for the pyrrolic type N-doped graphene. Implications of these findings to the design of Nano-Si-based Li-ion battery with high capacity and improved cycle life are also discussed. [ABSTRACT FROM AUTHOR]

A major research topic nowadays is to study and understand the functions of the increasing number of predicted genes that have been discovered through the complete genome sequencing of many plant species. With the aim of developing tools for rapid and convenient gene function analysis, we have developed a set of “pGate” vectors based on the principle of Golden gate and Gateway cloning approaches. These vectors combine the positive aspects of both Golden gate and Gateway cloning strategies. pGate vectors can not only be used as Golden gate recipient vectors to assemble multiple DNA fragments in a pre-defined order, but they can also work as an entry vector to transfer the assembled DNA fragment(s) to a large number of already-existing, functionally diverse, Gateway compatible destination vectors without adding additional nucleotides during cloning. We show the pGate vectors are effective and convenient in several major aspects of gene function analyses, including BiFC (Bimolecular fluorescence complementation) to analyze protein–protein interaction, amiRNA (artificial microRNA) candidate screening and as assembly of CRISPR/Cas9 (Clustered regularly interspaced short palindromic repeats, CRISPR-associated protein-9 nuclease) system elements together for genome editing. The pGate system is a practical and flexible tool which can facilitate plant gene function research. [ABSTRACT FROM AUTHOR]

Autophagy plays an important role in spinal cord ischemia reperfusion (I/R) injury, but its neuroprotective or neurodegenerative role remains controversial. The extent and persistence of autophagy activation may be the critical factor to explain the opposing effects. In this study, the different roles and action mechanisms of autophagy in the early and later stages after I/R injury were investigated in rats. The spinal cord I/R injury was induced by 14-min occlusion of the aortic arch, after which rats were treated with autophagic inhibitor (3-methyladenine, 3-MA) or agonist (rapamycin) immediately or 48 h following the injury. Autophagy markers, microtubule-associated protein light chain 3-II (LC3-II) and Beclin 1 increased and peaked at the early stage (8 h) and the later stage (72 h) after spinal cord I/R injury. Beclin 1 was mostly expressed in neurons, but was also expressed to an extent in astrocytes, microglia and vascular endothelial cells. 8 h after injury, rats treated with 3-MA showed a decrease in the hind-limb Basso–Beattie–Bresnahan (BBB) motor function scores, surviving motor neurons, and B-cell lymphoma-2 (Bcl-2) expression, and increase in the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL)-positive cells, Bcl-2-associated X protein (Bax), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) expression, and activation of microglia, while those treated with rapamycin showed opposing effects. However, 72 h after injury, rats treated with 3-MA improved the BBB scores, and the surviving motor neurons, and reduced the autophagic cell death, while those treated with rapamycin had adverse effects. These findings provide the first evidence that early activated autophagy alleviates spinal cord I/R injury via inhibiting apoptosis and inflammation; however later excessively elevated autophagy aggravates I/R injury through inducing autophagic cell death. [ABSTRACT FROM AUTHOR]

Alendronate-monoethyl adipate-(hydrazone)-doxorubicin conjugate ( ALN- MA-hyd- DOX) was synthesized to specifically deliver doxorubicin ( DOX) to bone tumor tissue. The binding kinetics of ALN- MA-hyd- DOX with hydroxyapatite ( HA) and natural bone were detected by using spectrophotometer. Cytotoxicity of ALN- MA-hyd- DOX on tumor cells was determined by MTT [3-(4,5-dimethylthiaol-2-yl)-2,5-diphenyl-tetrazolium bromide] method. The cellular uptake of ALN- MA-hyd- DOX was observed by using fluorescence microscopy. The in vivo antitumor activity of ALN- MA-hyd- DOX was investigated by using tumor-bearing nude mice model. The results indicated that ALN- MA-hyd- DOX was able to quickly bind with HA and natural bone. ALN- MA-hyd- DOX immobilized on the natural bone released more DOX in p H 5.0 medium than that in p H 6.0 or 7.4 medium. The cytotoxicity of ALN- MA-hyd- DOX toward A549 cells and MDA- MB-231/ ADR cells was greater than DOX. ALN- MA-hyd- DOX was rapidly uptaken by A549 cells and MDA- MB-231/ ADR cells. Compared with the same dose of free DOX, ALN- MA-hyd- DOX significantly decreased tumor volume of tumor-bearing nude mice. DOX mainly distributed in bone tumor tissue after ALN- MA-hyd- DOX was intravenously administered to tumor-bearing nude mice, whereas DOX distributed through the whole body after DOX was intravenously administered to tumor-bearing nude mice. These findings implied that the ALN- MA-hyd- DOX was a promising bone-targeted conjugate for treating bone neoplasms. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:2293-2303, 2015 [ABSTRACT FROM AUTHOR]

Abstract: Glutathione peroxidase 4 (Gpx4) is an antioxidant defense enzyme important in reducing hydroperoxides in membrane lipids and lipoproteins. Gpx4 is essential for survival of embryos and neonatal mice; however, whether Gpx4 is required for adult animals remains unclear. In this study, we generated a floxed Gpx4 mouse (Gpx4(f/f)), in which exons 2–4 of Gpx4 gene are flanked by loxP sites. We then cross-bred the Gpx4(f/f) mice with a tamoxifen (tam)-inducible Cre transgenic mouse (R26CreER mice) to obtain mice in which the Gpx4 gene could be ablated by tam administration (Gpx4(f/f)/Cre mice). After treatment with tam, adult Gpx4(f/f)/Cre mice (6–9months of age) showed a significant reduction of Gpx4 levels (a 75–85% decrease) in tissues such as brain, liver, lung, and kidney. Tam-treated Gpx4(f/f)/Cre mice lost body weight and died within 2weeks, indicating that Gpx4 is essential for survival of adult animals. Tam-treated Gpx4(f/f)/Cre mice exhibited increased mitochondrial damage, as evidenced by the elevated 4-hydroxylnonenal (4-HNE) level, decreased activities of electron transport chain complexes I and IV, and reduced ATP production in liver. Tam treatment also significantly elevated apoptosis in Gpx4(f/f)/Cre mice. Moreover, tam-treated Gpx4(f/f)/Cre mice showed neuronal loss in the hippocampus region and had increased astrogliosis. These data indicate that Gpx4 is essential for mitochondria integrity and survival of neurons in adult animals. [Copyright &y& Elsevier]

ROP GTPases (Rho-related GTPases from plant), a unique subgroup of the Rho family in plants, is a group of key regulators of different signaling pathways controlling plant growth and development, cell polarity and differentiation, and plant response against biotic and abiotic stresses. The present study determined the potential regulatory mechanism of potato ROP GTPase (StRac1) against Phytophthora infestans (P. infestans) infection. Protein secondary structure analysis indicated that StRAC1 is a Rho GTPase. The expression level of StRac1 was variable in different tissues of potato, with the highest expression in young leaves of both Shepody and Hutou potato varieties. After challenging with P. infestans , the expression level of StRac1 was higher in resistance varieties Zihuabai and Longshu 7 than in susceptible varieties Shepody and Desiree. StRAC1 fusion with GFP subcellularly localized at the plasma membrane (PM) in tobacco epidermal cells. The potato with transient or stable over-expression of CA-StRac1 (constitutively active form of StRac1)exhibited a dramatic enhancement of its resistance against P. infestans infections. The increased resistance level in transgenic potato was accompanied with elevated H 2 O 2 levels. Importantly, silencing StRac1 via virus-induced gene silencing (VIGS) in potato resulted in higher susceptibility to P. infestans infection than in control plants. In summary, our data reveal that StRac1 regulates potato resistance against P. infestans via positively modulating the accumulation of H 2 O 2. [ABSTRACT FROM AUTHOR]

The well-constructed Si nanostructure anode is essential for achieving high performance lithium-ion battery. In this report, void-buffered Si@TiO 2 /C microspheres are fabricated via a facile solid-liquid adsorption template technology followed by calcination process. Here, for the first time, the green and low-cost TiCl 4 solution is employed as the inorganic titanium precursor for synthesis of size-controllable TiO 2 shell. The void buffer can be controlled by the annealing temperature and concentration of the precursor of template. The Si@TiO 2 /C combines the merits of controllable void for releasing the mechanical stress, robust TiO 2 /C shell for building stable SEI film, high electronic conductivity for improving charge transfer. This specific structure is demonstrated to be effective in alleviating the volume effect during cycling process. When Si@TiO 2 /C microspheres are evaluated as anode of lithium-ion battery, a high reversible specific capacity of 1384 mA h g−1 is obtained after 100 cycles at 200 mA g−1. Even at a high current density of 500 mA g−1, a reversible capacity of 1038 mA h g−1 can still be retained after 400 cycles. The high-capacity electrochemical performance and easy preparation methods demonstrate the Si@TiO 2 /C microspheres are considered as a very promising anode material for next-generation lithium-ion batteries. • For the first time, the inorganic TiCl 4 solution is employed to synthesize size-controllable TiO 2 shell. • The Si@TiO 2 /C combines the merits of controllable void, robust TiO 2 /C shell and high electronic conductivity. • The composite exhibits excellent cycle performance. • The method provides a route for the synthesis of Si and other metal oxides composites. [ABSTRACT FROM AUTHOR]

The Li 4 Ti 5 O 12 /activated graphene nanoplatelets (Li 4 Ti 5 O 12 /a-GNPs) composites are prepared via a low-cost, green, one-pot hydrothermal process by using LiOH both as lithium source and activating agent for the first time. The LiOH solution concentration and hydrothermal time are optimized to obtain the pure Li 4 Ti 5 O 12 /a-GNPs. The synergistic effects of the nanosized Li 4 Ti 5 O 12 and the three-dimensional porous a-GNPs endow the composites with convenient lithium ion diffusion channels and efficiently conductive structures for electron and ion transport. As anticipated, the Li 4 Ti 5 O 12 /a-GNPs deliver an outstanding rate capability of 125 and 113 mA h g −1 at 80 and 100 C, respectively, and an excellent cycling stability with 90.21% capacity retention after 2000 cycles at 10 C. These results are much better than those of the Li 4 Ti 5 O 12 /GNPs and pure Li 4 Ti 5 O 12 , demonstrating Li 4 Ti 5 O 12 /a-GNPs are promising anode materials for lithium-ion batteries of high current density applications. [ABSTRACT FROM AUTHOR]

A new approach has been designed to convert typical Stöber silica spheres to Zn 2 Ti 3 O 8 (ZTO) hollow spheres with different shell thicknesses as anode materials for Lithium ion batteries. The morphologies, structures and synthesis process of ZTO hollow spheres are systematically investigated. X-ray diffraction (XRD) analysis shows that the good ZTO crystal is formed after being sintered at 500 °C for 2 h. The galvanostatic cycle tests exhibit excellent cycling stability, reversibility and low voltage. At a current density of 200 mA g −1 , the discharge specific capacities of 186.2 mAh g −1 , 173.6 mAh g −1 and 169.9 mAh g −1 have been achieved after 100 cycles, 200 cycles and 300 cycles, respectively. The superior electrochemical performance could be attributed to the hollow structure and characteristics of ZTO crystals. Cyclic voltammetry (CV) curves show symmetrical and stable redox peaks at 1.1 V and 1.5 V for ZTO hollow spheres after the first cycle. Electrochemical impedance spectroscopy (EIS) measurement analysis also indicates that ZTO hollow spheres as anode materials for LIBs have excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract: Pesticide exposure is a risk factor of Alzheimer''s disease (AD). However, little is known about how pesticide exposure may promote AD pathogenesis. In this study, we investigated the effects of paraquat pesticide exposure on β-amyloid (Aβ) levels and cognition using wild-type (WT) mice and β-amyloid precursor protein (APP) transgenic mice. Our results showed that wild-type mice and APP transgenic mice after paraquat exposure had increased oxidative damage specifically in mitochondria of cerebral cortex and exhibited mitochondrial dysfunction. Moreover, the elevated mitochondrial damage was directly correlated with impaired associative learning and memory and increased Aβ levels in APP transgenic mice exposed to paraquat. Furthermore, overexpression of peroxiredoxin 3, a mitochondrial antioxidant defense enzyme important for H2O2 removal, protected against paraquat-induced mitochondrial damage and concomitantly improved cognition and decreased Aβ levels in APP transgenic mice. Therefore, our results demonstrate that mitochondrial damage is a key mechanism underlying cognitive impairment and elevated amyloidogenesis induced by paraquat and that enhanced removal of mitochondrial H2O2 could be an effective strategy to ameliorate AD pathogenesis induced by pesticide exposure. [Copyright &y& Elsevier]

• In total, 66 ROPs were identified in 6 Solanaceous species (SolROPs). • Eleven AtROPs and 66 SolROPs fall into five distinct clades (I-V). • A novel and systematic gene nomenclature was proposed for all ROPs in this study. • SlROP-II.1 and its homologues NbROP-II.1 and CaROP-II.1 function in resistance to P. capsici. • In addition, NbROP-II.1 is also involved in regulating plant growth and development. Small GTPases function as molecular switches to active or inactive signaling cascades via binding or hydrolyzing GTP. A type of plant specific small GTPases, the ROPs are known to be involved in plant growth, development and immunity. We determined whether ROPs are conserved in Solanaceous species and whether they are involved in plant growth, development and resistance against Phytophthora capsisi. In genome-wide screening, a total of 66 ROPs in six Solanaceous species (SolROPs) were identified, including 16 ROPs in Solanum tuberosum L. (potato), 9 in Solanum lycopersicum L. (tomato), 5 in Solanum melongena L. (eggplant), 9 in Capsicum annuum L. (pepper), 13 in Nicotiana benthamiana Domin and 14 in Nicotiana tabacum L. (tobacco). Phylogenetic analysis revealed that 11 AtROPs and 66 SolROPs fall into five distinct clades (I-V) and hence a novel and systematic gene nomenclature was proposed. In addition, a comprehensive expression analysis was performed by making use of an online database. This revealed that ROP genes are differentially expressed during plant growth and development. Moreover, gene expression of SlROP-II.1 in S. lycopersicum could be significantly induced by P. capsici. Subsequently, SlROP-II.1 and its homologues in N. benthamiana and C. annuum (NbROP-II.1 and CaROP-II.1) were selected for functional analysis using virus-induced gene silencing. Infection assays with P. capsici on silenced plants revealed that SlROP-II.1, NbROP-II.1 and CaROP-II.1 play a role in P. capsici resistance, suggesting conserved function of ROP-II clade across different Solanaceous species. In addition, NbROP-II.1 is also involved in regulating plant growth and development. This study signified the diversity of Solanaceous ROPs and their potential roles in plant growth, development and immunity. [ABSTRACT FROM AUTHOR]